Sökning: "power amplifier PA"
Visar resultat 16 - 20 av 30 avhandlingar innehållade orden power amplifier PA.
Sammanfattning : The wireless market has experienced a remarkable development and growth since the introduction of the first modern mobile phone systems, with a steady increase in the number of subscribers, new application areas, and higher data rates. As mobile phones and wireless connectivity have become consumer mass markets, the prime goal of the IC manufacturers is to provide low-cost solutions. LÄS MER
Sammanfattning : This doctoral dissertation presents a study of linear radio transmitters based on the combined analog locked loop universal modulator (CALLUM) approach. Linear architectures such as CALLUM are very attractive for power-efficient operations, since they have no fundamental limitations prohibiting a 100% efficiency for all envelope levels, without sacrificing the potential of a linear transmission. LÄS MER
Sammanfattning : Nowadays the main driving parameters for the research in radio transmitters in wireless infrastructure are energy efficiency, frequency agility, and integration.This thesis presents new solutions at the device waveform-, circuit-, and transmitter level which exploit the inherent high efficiency potential of switch-mode power amplifiers (SMPAs) for realization of energy efficient, wide-band, highly integrated transmitters for wireless communication applications. LÄS MER
Sammanfattning : SiC MESFETs and GaN HEMTs posses an enormous potential in power amplifiers at microwave frequencies due to their wide bandgap features of high electric field strength, high electron saturation velocity and high operating temperature. The high power density combined with the comparably high impedance attainable by these devices also offers new possibilities for wideband power microwave systems. LÄS MER
Sammanfattning : The increasing use of mobile networks as the main source of internet connectivity is creating challenges in the infrastructure. Customer demand is a moving target and continuous hardware developments are necessary to supply higher data rates in an environmentally sustainable and cost effective way. LÄS MER